JPH0264814A - File control system for plural files in one magnetic tape volume - Google Patents

Abstract

PURPOSE:To refer to information without taking much input time when information of files in a magnetic tape is much by adding a file control label to the magnetic tape. CONSTITUTION:When three is no label for controlling plural files at the back of a volume start label in the one magnetic tape volume, a means for generating and inputting the label for controlling plural files in the magnetic tape volumes generates the area of the file control label. When there is the file control label, the file control label is inputted and stores it in a work area. All file information can be referred by inputting and outputting them from all file information of the file control label inputted by the means. Thus, the more the number of files, the shorter a reference time can become.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a computer system (herein, a method for managing a plurality of files in one magnetic tape volume).

[Prior Art] Conventionally, in a method of managing multiple files in a magnetic tape volume, a data area surrounded by a file start label and a file end label is treated as one file, and the first file from the beginning, the second file from the beginning, etc. File...
・File start label, file end label (Thus, the file area was delimited, and it was assumed that no file existed after the tape mark indicating the end of data.

For example, if there are two data areas surrounded by a file start label and a file end label, and you want to store data in the second file, the data area surrounded by the first file start label and the first file end label should be stored in the second file. Skip the data area, position it at the start label of the second file, and store the data. After storing, it outputs a second file end label and a tape mark indicating the end of the data, and then exits.

Also, when collecting file information on a magnetic tape volume, read the file start label and file end label of each file for which you want to collect file information.
Information on each file was collected.

[Problem to be solved by the invention]

In the conventional method described above, a data area surrounded by a file start label and a file end label is recognized as one file, and it is recognized that no file exists after the tape mark indicating the end of data.

For example, if multiple files are stored on a magnetic tape, you try to add data after the last file, but the first file is incorrectly specified to add this data. In this case, the first file start label is located, the data is stored, and after the data is stored, the file end label and tape mark indicating the end of the data are output and the process ends, so all files after the second file are corrupted. I can't help it.

Also, to obtain file information (file name, block name, number of blocks, etc.), you must refer to the file start label and file end label of each specified file. The disadvantage is that the larger the number, the longer the reference time will be.

[Failure to solve the problem]

The present invention is a method for managing multiple files in a magnetic tape volume. If there is no label for managing multiple files, an area is created, and if there is a label, the label is input (this task A means for creating and inputting a label for managing multiple files in a magnetic tape volume to be stored in a magnetic tape volume, and a means for creating and inputting a label by the label creation input means when it is specified that a file is to be stored in a magnetic tape volume. and means for storing the file in a magnetic tape volume, which obtains file information from the inputted label and stores it in a data area of the designated file; A means for updating the label for managing multiple files in a magnetic tape volume when the data storage state is changed, and a means for managing multiple files when a file is specified to be retrieved from the magnetic tape volume. means for extracting a file from a magnetic tape volume, from the file information on the label of the specified file, from the first data area to the last data area; In this case, the apparatus includes means for referring to file information in the magnetic tape volume from the label for managing a plurality of files in the magnetic tape volume.

〔Example〕

Next, the present invention will be explained in detail with reference to the drawings.

FIG. 1 is a diagram showing the relationship between means for realizing a file management system for a plurality of files in a magnetic tape system according to the present invention.

FIG. 1 shows an embodiment in which multiple files in a magnetic tape volume are managed by providing labels for managing multiple files in the magnetic tape volume.
A label for managing multiple files (hereinafter referred to as "
If there is no file management label, create an area for the file management label, and if there is a file management label, enter the file management label and store it in the work area. Means for creating and inputting labels for managing multiple files 1
If data of another file is specified to be stored in the file area of the magnetic tape volume, the data of another file is stored in the specified file area, and when the data cannot be stored in the specified file area. means 2 for storing a file in a magnetic tape volume, which locates the file in an empty data area in the file management label and stores the remaining data that could not be stored; and means 2 for storing the data on the magnetic tape volume. Means 3 for updating labels for managing multiple files in a magnetic tape volume when the status is changed; and file management when a specified file area is specified to be extracted from the magnetic tape volume. Means 4 for extracting a file from a magnetic tape volume tp, which locates a file in a specified file area based on the information on the label and extracts the amount of data in all data areas of the specified file; If the file information is specified to be referenced, the stored file information can be referenced from the file management label.The file information in the magnetic tape volume can be referenced from the label for managing multiple files in the magnetic tape volume. It is composed of means 5.

The functions of each of the above means, the relationship between each means, and an example are explained in the second section.
Figure I is shown and described below.

For example, file A is stored in data area 1.3 in a magnetic tape volume, and file B is stored in data area 2.4.
．． When storing file X in the area (data area 1.3) of file A (data area 1.3), means 1
．． This is realized by 2.3. The implementation method is shown below.

First, method 1 for creating and inputting file management labels
will be explained with reference to chart 70 of FIG.

Position the label at the beginning of the magnetic tape volume, insert the label (means IA), and if it is the first label of the polynym (
Means IB), enter the next label positioning label. If it is not a volume start label but a file management label (means IC), the file management label is stored in the work area (means IE).

If it is not a file management label, create a file management label area (means ID).

Next, when it is specified that file X is to be stored in the area of file A (data area 1.3), control is transferred to means 2 for storing the file in the magnetic tape volume.

The processing of means 2 will be explained with reference to FIG.

When adding files (files A and B remain as they are, file X stores an empty data area), method 2
When passing control to F and not adding a file (store file X in the data area of file A), use method 2.
Transfer control to B (means 2A).

Next, when all the contents of file X have been stored, control is passed to means 2E, and when storage has not been completed, control is passed to means 2C (means 2B).

Next, when the data is stored in the data area equivalent to two data areas of the specified file A, control is passed to the means 2F,
If the contents of the file X are not stored in two data areas of the specified file A, the means 2C) transfers control to the means 2D, and stores the contents of the file X in the data area 1 or 3 of the file A. The storing means 2D) counts up a counter for pointing to data area 01 or 3 of the file A, and passes control to the means 2B (means 2F).

If the means 2 or the means 2F to which control has been passed from the means 2C has finished storing all the contents of the file X, it passes the control to the means 2E, and if the storage has not been completed, it passes the control to the means 2G. Means 2B) stores the contents of file (Means 2H).

Next, the means 21 creates file information of the stored file X according to the file management label format shown in FIG. 7, stores it in a work area for each file, and passes control to the means 3.

Means 3, which has been given control from means 2I, stores 7'l-
7 Close the isle X, locate the file management label in the magnetic tape volume (means 3A), update the file management label to the changed file information in means 2, and follow the format of the file management label shown in FIG. , one area of the file management label is stored (means 3B).

The above is the detailed process for storing file X in the area of file A.

As another example, file A in a magnetic tape volume
, B are stored in the data area 1.3 and the data area 2.4.6, respectively, and when a designation is made to take out the file B, this is realized by means 1.4. The implementation method is shown below.

First, since the means 1 for creating and inputting a file management label has been described above, the means 4 for extracting files from a magnetic tape volume will be explained with reference to the flowchart of FIG.

If the data area of the file B data area number 3 is taken out, it is terminated, and if it is not taken out, the control is passed to the means 4B 4A), data area 2.4.6
In this order (means 4B for extracting this data area) and means 4C for counting up the number of processed data areas, control is passed to means 4A.

As another example, assume that file A%B is stored in data area 113 and data area 2.4.6 (respectively) in a magnetic tape volume, and refer to information on all files stored therein. When specified, it is realized by means 1.5.The realization method is shown below.

First, method 1 for creating and inputting a file management label (
Since the details have been described above, the means 5 for referencing file information from the magnetic tape volume will be explained below.

By printing out all the file information of the file management label input by means 1, all the file information can be referred to.

〔Effect of the invention〕

As described above, in the method of the present invention, by attaching a file management label to a magnetic tape, the more file information on the magnetic tape, the less time it takes to input it and the more it can be referenced.

Furthermore, even if you try to store data in a certain file by specifying it incorrectly, only the incorrectly specified file will be destroyed, but the files after the incorrectly specified file will be protected.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration and one embodiment of the present invention, FIG. 2 is a diagram showing the relationship between each means and between a file management label and a file in a magnetic tape volume, and FIG. 3 is a diagram showing the processing in means 1. FIG. 4 is a flowchart showing the processing in means 2, FIG. 5 is a flowchart showing the processing in means 3, FIG. 6 is a prochart showing the processing in means 4, and FIG. 1 is a diagram showing the format of a file management label. In the diagram, 1... Means for creating and inputting a label for managing multiple files in a magnetic tape system;
2... Means for storing files in a magnetic tape volume; 3... Means for updating labels for managing multiple files in a magnetic tape volume;
4...Means for retrieving files from the magnetic tape volume, 5...Means for referencing file information in the magnetic tape volume, 6...Means for retrieving files from the magnetic tape volume, 6...Means for retrieving files from the magnetic tape volume, 6...Means for retrieving files from the magnetic tape volume, A magnetic tape on which files are managed. Agent Patent Attorney Shinsuke Honjo

Claims (1)

[Claims] In a method for managing multiple files in a magnetic tape volume, if there is no label for managing multiple files, an area is created, and if there is a label, the label is input and a work area is created. means for creating and inputting a label for managing multiple files in a magnetic tape volume to be stored, and a means for creating and inputting a label by the label creation input means when a file is specified to be stored in a magnetic tape volume; means for storing a file in a magnetic tape volume that obtains file information from the label and stores it in a data area of a designated file; means for updating the label for managing multiple files in the magnetic tape volume when a file is retrieved from the magnetic tape volume; and file information on the label for managing multiple files when a file is specified to be extracted from the magnetic tape volume. A method for extracting a file from a magnetic tape volume, which extracts the data from the first data area to the last data area of a specified file from the magnetic tape volume. A file management method for a plurality of files in a single magnetic tape volume, comprising means for referring to file information in the magnetic tape volume from the label for managing a plurality of files in the magnetic tape volume.